Electrical contact terminal posts are known which can be electrically connected to printed circuit boards by insertion through plated through-holes of a board and secured therein without solder. Such terminal posts have compliant mounting sections therealong which bear against and are spring biased inwardly by the plated walls of the through-holes, where the spring force is high enough that assured mechanical gripping is maintained, as well as assured electrical connection being established.
Terminal posts such as those of U.S. Pat. No. 4,186, 982 are formed from solid bar stock having a square cross-section of standard size, usually 0.025" square or 0.045" square. Those of U.S. Pat. Nos. 4,017,143; 4,076,356; 4,166,667; 4,191,440; and 4,381,134 have solid post contact sections and adjacent C-shaped compliant mounting sections formed of thinner metal stock than that of the post contact sections, requiring a milling operation prior to stamping the blank. The C-shaped section offers spring characteristics which are enhanced by reducing the thickness of the arms of the C-shape.
Protuberances are sometimes used along the C-shaped compliant mounting sections to break through surface oxides on the plating material for good electrical connection, as disclosed in U.S. Pat. No. 3,783,433. Axially extending ridges or ribs are used in U.S. Pat. No. 4,076,356 to actually penetrate into the plating material as also taught in U.S. Pat. Nos. 3,416,122 and 4,186,982.
It is desirable to form a terminal from relatively thin sheet metal stock of uniform thickness to reduce the metal content of the terminal and facilitate creating desired contact section structures on an end thereof, and eliminate the necessity of milling operations.
It is further desirable to form such a terminal to have protuberances to establish an assured electrical connection with the internal surface of a plated through-hole.